Preparation of naphthenic alcohols



United States Patent O PREPARATION OF NAPHTHENIC ALCOHOLS Charles A. Cohen, Roselle Park, and Louis A. Mikeska,

Westfield, N. J., assignors to Esso Research and Engineering Company, a corporation of Delaware No Drawing. Application December 22, 1951, Serial No. 263,007

1 Claim. (Cl. 260-617) This invention relates to an improved process for preparing water-soluble sulfates especially suited for use as detergents. More particularly, this invention relates to an improved process for preparing eifective water-soluble sulfate detergents in which the sulfate portion is linked to a naphthenic residue through a methylol group.

Water-soluble synthetic detergents have generally consisted of either alkyl aryl sulfonates, alkyl sulfates, and non-ionic types of which a polyethylene oxide condensation product of an alkyl phenol is representative. These materials have failed to supply the ever-increasing demand for water-soluble detergent products.

This invention provides a method of preparing watersoluble detergents. The method. comprises chlorinating a specific, relatively aliphatic and aromatic free naphthenic oil fraction; dehydrochlorinating the product; oxonating and reducing the resulting olefin from the previous step so as to obtain a naphthenic alcohol; sulfating the alcohol; and neutralizing the sulfated alcohol so as to obtain the water-soluble detergent product.

The product prepared by the process of this invention is distinct from all others hitherto made in that the sulfate portion of the detergent is linked to a naphthenic or alicyclic residue through a methylol group. The naphthenic residue can consist of completely hydrogenated cyclic hydrocarbons containing 5 or 6 carbons in the ring and may be alkylated with either straight chain or branched chain alkyl derivatives in one or more positions.

The nature of the naphthenic oil fraction utilized is extremely important. The process requires a relatively olefin, normal parafiin. and aromatic free naphthenic fraction. These naphthene concentrate oils may be prepared by the well-known exhaustive sulfuric acid treatment of a petroleum distillate from .selectedsources followed by neutralization, washing and distillation or stripping to obtain the desired oil. The oil after this treatment contains no more than about 5 weight per cent normal paraffins. The boiling point of the oil utilized is in the range of from 200 C. to 320 C. with a molecular weight in the range of 175 to 225. Fractions below this range yield products of insufficient detergency, and above yield products of insufiicient solubility. The naphthenes fallingin this boiling point and molecular weight range are therefore rather complex in nature, and probably contain fused ring components, alkyl side chains, etc. These compounds would seem particularly adapted for 2,734,923 Patented Feb. 14,1956

the production of the water-soluble detergents of this invention. The presence of more than a relatively small amount of olefins, normal parafilns and aromatics in the feed stock prior to chlorination results in the formation of undesirable polymeric materials, unstable chlorinated products and poor yields in the subsequent steps of dehydrochlorination and oxonation. Oils of Columbian or Coastal origin having high naphthenic content give extremely good results in the process of this invention;

In accordance with the process of this invention the specific oil fraction after treatment to remove olefins and aromatics is subjected to a chlorinating operation by passing gaseous chlorine into the liquid mixture while maintaining the temperature of the mixture substantially low, preferably below C. The passage of chlorine into the naphthenic mixture is continued until the gain in weight of the hydrocarbon material indicates that the chlorination reaction has proceeded to the extent desired. A ratio of 0.5 mol (one atomic We ght) of chlorine per I mol of hydrocarbon has been found to effect a satisfactory chlorination of the hydrocarbon; Chlorination in excess of the indicated level results, on subsequent dehydrochlorination, in the production of undesirable dienes which polymerize to high boiling compounds.

When the increase in weight of the white oil indicates that chlorination has proceeded to the desired level, the entire body of the chlorinated material is subjected to dehydrochlorination to obtain a cycloolefinic product. This dehydrochlorination is conducted in liquid phase by conventional means, e. g., thermally, by aqueous alkali, by alcoholic KOH, by alkali in glycols, or catalytically through the use of catalysts, such as barium chloride or amines, such as quinoline and collidine, etc., depending upon manipulative advantages. When the dehydrochlorination is done by thermal means alone, the'upper temperature limit is 320 C. Theother means of dehydrochlorination utilize an upper temperature level of 300? C. and usually result in less undesirable color formation.

The gaseous HCl is thus driven ofl in the case of thermal dehydrochlorination, leaving a liquid, predominantly monoolefinic, product. The chlorination-dehydrochlorination treatment results in the obtaining of a' cyclic olefin which is especially suited for oxonation and the ultimate production of the indicated water-soluble detergents. If dienes are present as indicated by the bromine number, these dienescan be removed by reaction with maleic anhydride' prior to sulfation; v

The naphthenic olefin is then oxonated by'the wellknown Oxo process for the production of alcohols (see, e. g., U. S. Patent 2,327,066 and U. S. Bureau of Mines Publication R1 4270, Critical Review of Chemistry of the Oxo Synthesis, etc. 1948). The term Oxo process is well understood in the art as referring to a process wherein an olefin feed is first reacted or oxonated with carbon monoxide and hydrogen at a temperature between and 250 C.,. and under a pressure of about to 400 atmospheres in the presence of a cobalt or similar catalyst, which may be introduced in the form of a fatty acid salt, to form aldehydes. As an illustration of a ture.

The aldehydes so formed are then catalytically hydrogenated to form the desired alcohols as follows:

acid, oleum, sulfur trioxide, sulfur trioxide and liquid S02,

bromand chlor-sulfonic acids in ethyl ether, etc., and their mixtures. Solvents may be used, such as ethyl ether, light hydrocarbons such as hexane, heptane, low-boiling petroleum ethers, of chlorinated solvents, etc. The sulfating agent may be added to the alcohol or vice-verse with the temperature kept in the range of 20 to 70 C.

The amount of sulfating agent employed varies from 100 'mol per cent based on the alcohol content of the feed, to

an excess equivalent to roughly 1.5 times the weight of .sodium sulfate per unit weight of sodium alcohol sulfate formed, on complete neutralization of the sulfation mixa methylol group.

The water-soluble sulfates are subsequently neutralized usually with caustic soda or soda ash and drum dried. Other neutralizing agents known in the art can also be employed. Unchanged hydrocarbons can be removed by extraction with solvents such as low-boiling naphtha, etc.

The following examples are given to illustrate this invention, and include both the processing of the naphthenic 'oils according to this invention and test results on the products as water-soluble detergents.

. EXAMPLE I.--PREPARATION OF FEED STOCK A Colombian gas oil having a boiling range of between 200 and 320 C. by Engler distillation and having in addition the following inspections:

Specific gravity .8633.

Kinematic viscosity at 100 F 2.99 centistokes. Cloud point 26 F.

ASTM pour below 62.2 C. Aniline point 56 C. Neutralization number 4.32 mg. KOH/ gm.

was treated in three portions with a total of-23% by volume of fuming sulfuric acid containing 25 dissolved S03, the sludge formed at the end of each acid treat withdrawn and the sour oil equal to 78% of the original distillate neutralized with 20% sodium hydroxide, water washed to remove neutralization products, steamed with superheated steam for twenty minutes at a temperature of 115 C., and finally dried by percolation through 30-60 mesh Attapulgus clay. Theacid treated oil showed the following inspections:

The oil was then distilled under reduced pressure through I a 15-plate fractionating column using a 2/1 reflux ratio and a 90% heart cut boiling between and 95% of the charge was taken overheadbetween the temperature limits, extrapolated to atmospheric pressure, of 243-296 C. Molecular weight determinations showed this cut to con- The 'sulfation results in the sulfate portion of the molecule being linked to the naphthenic residue through sist predominantly of a mixture of C14C15 naphthenic hydrocarbons. It' was entirely free of unsaturatesand centi-equivalents per gram.

contained less than a few per cent of normal paralfinic hydrocarbons and no aromatic hydrocarbons.

EXAMPLE II.CHLORINATION OF FEED STOCK 1414 grams of the acid treated gas oil prepared in Example I was chlorinated under the influence of ultra-violet light with a fast stream of chlorine at a temperature between 45-50" C. over a period of 1 hour. After removal of dissolved hydrogen chloride and excess chlorine by blowing with a stream of dry nitrogen the oil was found to have gained 265 grams of chlorine. The crude chlorinated material was water washed to remove traces of HCl and then distilled under high vacuum. The major portion boiling between to 150 C. at 0.35 mm. of Hg was analyzed for chlorine and found to contain 21.46 weight per cent chlorine.

EXAMPLE III.-DEHYDROCHLORINATION OF CHLORINATED FEED STOCK EXAMPLE IV.OXONATION OF OLEFIN FEED STOCK 357 grams of naphthenic olefin from Example III was dissolved in hexane and oxonated with a mixture of carbon monoxide and hydrogen with cobalt oleate as oxonation catalyst. At the completion of the oxonation 'run, the oxo aldehyde was reduced with nickel catalyst. Removal of the hexane gave 311 grams of crude product having a hydroxyl value of 0.143 centi-equivalents per gram. The crude product was accordingly esterfied with excess of boric acid which gave 8 ml. of water of esteri- 'fication. The borate ester was then topped under reduced pressure to a bath temperature of 280 C. and a vapor temperature of 130 C. The distillate which was hydrocarbon in nature was discarded and the remaining borate ester decomposed by refluxing with water for 1% hours. The purified alcohol which separated was water washed to remove acidic material and then distilled under high vacuum yielding 91.5 grams of a product boiling between -115- C. at a pressure of 0.075 mm. of Hg. The

purified product showed a hydroxyl value equal to 0.4028

EXAMPLE V.SULFATION OF NAPHTHENIC ALCOHOL 30.7 grams of the alcohol prepared in the preceding example were dissolved in 60 ml. of anhydrous ethyl ether and added dropwise at a temperature of 10-12 C. to 16.8 grams of chlorosulfonic acid which had been previouslycomplexed with 35 ml. of anhydrous ethyl ether at a temperature of 0 C. After all of the alcohol had been added to the acid, the mixture was stirred for an additional half-hour at 10 C. and then poured into a mixture of 200 grams of ice and 30 ml. of 30% sodium hydroxide. The neutralized sulfate was then evaporated on a steam bath to remove ether and then sufficient 99% isopropyl alcohol added to bring the total volume to 480 ml. When cool, the solution of the sulfate in dilute alcohol was extracted three times with 200 ml. portions of petroleum ether so as to remove unsulfated product and then. dehydrated with excess sodium carbonate. Evaporation of the petroleum ether extracts yielded 0.85

gram of unsulfated material. Analyses of the dehydrated of 98%. A quantity of the alcoholic solution containing 37.7 grams was then taken, to which was then added 56.5 grams of sodium sulfate. The mixed solution containing 40% of active ingredient was then drum dried to a whitewater-soluble fiakey product.

EXAMPLE VI.--EVALUATION OF DETERGENT Evaluation of the 40% active detergent prepared in Example V is shown in Table I below:

Table 1.-Launder0meter evaluation of naphthenic alcohol sulfate [Artificially soiled Indian Head muslin by Van Zile used in evaluation soiled cloth had average reflectivity of 21.8% compared to MgO.]

\VASHED IN lVIEDIUM-HARD \VATER CONTAINING 120 P. P. M. HARDNESS EQUIVALENT TO @100 WASHED IN HARD WATER CONTAINING 360 P. P. M. HARD- NESS EQUIVALENT TO 08003 532 Eflielency Washed in Water (No detergent) 21.5 Washed in Water Detergent:

0.5% 25. 9 122 Washed in Water Commercial Sodium Lauryl Sulfate 0.5% 25. 1 100 These results indicate that the detergents prepared by the method of this invention were superior in both reflectivity and efficiency as compared with one of the best known and most favorably accepted commercial detergents.

Products from the process of this invention, as stated above, are unique in that the sulfate portion is linked neither to an alkyl nor an aromatic residue, but is attached directly to a naphthenic residue through a methylol group. The water-solubility and effective detergent action makes them extremely valuable.

It is to be understood that this invention is not limited to the specific examples, which have been oifered merely as illustrations, since modifications may be made without departing from the spirit of this invention.

What is claimed is:

An improved process for preparing a naphthenic alcohol product suitable as an intermediate in the production of highly eflLicient water-soluble primary naphthenic alcohol sulfate detergents which comprises chlorinating a naphthenic hydrocarbon fraction which is substantially free of olefins, normal paraflins and aromatics, and which has a molecular weight in the range of about 175 to 225, and a boiling range of about 200 to 320 C., dehydrochlorinating the thus chlorinated naphthenic hydrocarbon fraction to produce an olefinic naphthenic product, thereafter subjecting said olefin product to a reaction with carbon monoxide and hydrogen in the presence of a cobalt catalyst at a temperature between about to 250 C., and a pressure of about to about 400 atmospheres to produce an aldehyde product having one more carbon atom than said olefinic material, thereafter hydrogenating said aldehyde product to produce a primary alcohol product, said primary alcohol product comprising a mixture of naphthenic alcohols.

References Cited in the file of this patent UNITED STATES PATENTS 2,000,994 Schrauth May 14, 1935 2,042,410 Peirce May 26, 1936 2,081,865 Elbel May 25, 1937 2,327,066 Roelen Aug. 17, 1943 

